281440 has 24 divisors (see below), whose sum is σ = 665280. Its totient is φ = 112512.

The previous prime is 281431. The next prime is 281509. The reversal of 281440 is 44182.

281440 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 720 + ... + 1039.

It is an arithmetic number, because the mean of its divisors is an integer number (27720).

2²⁸¹⁴⁴⁰ is an apocalyptic number.

281440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

281440 is an abundant number, since it is smaller than the sum of its proper divisors (383840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

281440 is a wasteful number, since it uses less digits than its factorization.

281440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1774 (or 1766 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 281440 is about 530.5091893643. The cubic root of 281440 is about 65.5332853375.

The spelling of 281440 in words is "two hundred eighty-one thousand, four hundred forty".